Abstract
The basaltic rocks from the central and southern islands of the New Hebrides-Aneityum, Tanna, Erromango, Efate, Emae, Tongoa and Epi, have geochemical features typical of island arc volcanics. They are enriched in LILE and depleted in Zr, Hf, Nb and Ta compared to N-type MORB. The rocks were derived from a similar upper mantle source as N-type MORB but with a higher degree of partial melting. In addition their source was enriched in LILE (K, Rb, Sr, Ba and LREE) probably by migrating hydrous fluids released during the dehydration of the subducted oceanic slab. The basalts from Futuna island which is located farther from the trench, display characteristics typical of calc-alkaline rocks. The Futuna basalts were generated from a different LILE-enriched upper mantle source. It seems that this upper mantle source was modified by interaction with partial melts from the subducted oceanic lithosphere.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.